Analysis of income inequality in Japan using individual data from the Comprehensive Survey of Living Conditions
DOI:
https://doi.org/10.25071/1874-6322.40637Keywords:
Income inequality, Equivalent disposable income, Gini coefficient, Top income share, Relative poverty rateAbstract
This study analyses trends in income inequality in Japan from 1991 to 2021 using microdata from the Comprehensive Survey of Living Conditions (CSLC), supplemented by the National Survey of Family Income, Consumption and Wealth (NSFICW) and tax records. Key indicators examined include the Gini coefficient, top income shares, and the relative poverty rate. While total income per household has declined, the consistent reduction in household size over the period underscores the importance of analysing equivalent income, which adjusts for household composition. The study finds that despite prolonged economic stagnation since the 1990s, overall income inequality has remained relatively stable, particularly when measured by the Gini coefficient for equivalent disposable income. Equivalent income declined in the 2000s but began to rise again after 2015, possibly reflecting economic recovery measures such as Abenomics. To better capture high-income groups, the study incorporates data from the Sample Survey for Self-Assessment Income Tax (SSSAIT), which reveals a recent increase in the top 1% and 0.1% income shares. The analysis also highlights persistent asset inequality, rising household savings, and Japan’s relatively high poverty rate despite moderate Gini coefficients.
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